In recent years, various manufactured articles have been produced by producing a slurry containing an inorganic powder of electroconductive particles, ceramics, glass, a phosphor or the like and a binder for molding, molding a slurry mixture, and sintering a molded product. As binders for molding, polyvinyl butyral (PVB), ethyl cellulose (EC), carboxymethyl cellulose (CMC), polyvinyl alcohol (PVA), acrylic polymers, and the like have been used. Although it is preferable that the binder component completely disappears during sintering, the above-mentioned binders are hardly decomposable, so that binder residues remain in the molded ceramics by merely heating alone, which cause worsening effects to the performance of the ceramics. Therefore, a method of supplying oxygen during the sintering and completely combusting a binder to allow the binder to disappear has been employed.
However, when oxygen is present under high-temperature conditions during the sintering, the inorganic components would be undesirably modified, so that the performance of the sintered bodies is lowered in some cases, and in many cases after the sintering, a further step of sintering under reductive atmosphere would be necessitated. Therefore, a binder which can disappear without supplying oxygen during the sintering has been desired.
Further, since the above-mentioned binder exothermically decomposes, it would be difficult to sinter in a large amount at one time while controlling the temperature of the sintering furnace.
As binders capable of endothermically decomposing without requiring oxygen during the sintering, aliphatic polycarbonate resins such as polypropylene carbonate and polyethylene carbonate have been studied. However, in some cases the decomposition temperatures of these resins are too low depending upon the production processes (see, Patent Publication 1). In view of the above, as a solving means thereof, a method of elevating a decomposition temperature by capping a molecular chain end has been known (see, Patent Publication 2, Non-Patent Publication 1).